1. February 6, 2012 At the end of today, you will be able to solve quadratic equations by factoring. Warm-up: Factor 1.x 2 – 11x 2. x 2 – 6x – 16 3. 2x 2 + 7x – 15 Turn in Factor Review HW and Test Corrections!

2. HW Questions?

3. Lesson 6.3 Solving Quadratic Equations by Factoring Example 1: Solve 2x 2 + 7x = 15 1. Always equate to zero. - 15 2x 2 + 7x – 15 = 0 2. Factor 3. Set each factor = 0, and solve for x. 2x 2 + 10x – 3x – 15 = 0 2x(x + 5) – 3(x + 5) = 0 (x + 5)(2x – 3) = 0 x + 5 = 0 2x – 3 = 0 - 5 x = -5 + 3 2x = 3 x = 3/2 Check your answers by plugging it back in!

4. Practice Solving By Factoring 1.x 2 – 3x – 28 = 0 2.x 2 = 81 3.4x 2 = -3x 1. Always equate to zero. 2. Factor 3. Set each factor = 0, and solve for x.

5. What have we learned so far? A quadratic (x 2 ) is a parabola The axis of symmetry cuts it half. x = -b/(2a) The vertex is the max or min point. When you solve a quadratic, you are finding the roots, zeros or the x-intercepts.

6. HW 6.3 Pg. 304 #14-30 even, #63-68all Solve #14-30 14. x 2 + 5x – 24 = 030. -2x2 + 12x – 16 = 0 16. x 2 = 25Simplify #63-68 18. x 2 + 3x = 1863. 20. 3x 2 = 5x64. 22. x 2 + 36 = 12x65. 24. 4x 2 + 7x = 266. 26. 4x 2 + 8x = -367. 28. 9x 2 + 30x = -1668.

7. Valentine’s Extra Credit Heart on Graphing Calculator Draw a heart on your graphing calculator. Hint: Solve for y You must show your work to get the credit.